In a wireless local area network (WLAN), there may be one or more portable electronic devices communicating with other devices on the network. Such devices may be powered by a battery in order to provide mobile operation of the device. However, operating on a wireless local area network may entail occasional or frequent communications between devices operating on the network, for example according to a protocol of a wireless local area network communication standard. Such communication involves operation of the radio transceiver of the device, thereby consuming some amount of power and reducing the battery life of the device. One difficulty in reducing power consumption in a portable device acting as a client node on the network is that a wireless LAN connected device consumes significant power when its radio receiver is active but not receiving useful data, and the device may have no a priori knowledge of when data will arrive at the supporter node for transmission the client node device. The problem is then one of coordinating timing, such that the client node is awake, that is has its receiver active, for a shorter or the shortest possible proportion of time in order to receive data packets. It would therefore be desirable to communicate over a wireless local area network according to a protocol that provides at least some power saving for such portable electronic devices.
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